Dan Bachar

Distributed systems engineer. I build networked, backend and peer-to-peer systems — from protocol design to production.

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Work

  1. 2023–2025

    Lead Developer & Senior Distributed Systems Researcher

    Siemens AG, Munich

    • Led R&D of demonstrators for distributed industrial IoT edge systems in the EU-funded Edgeless project.
    • Designed a graph-based configuration tool for edge network topology (ReactFlow).
    • Built a cluster management platform for industrial computers with system-level snapshotting.
    • Built a 6G satellite communication handover system for next-generation EU rail.

  2. 2022–2023

    Frontend Tech Lead

    Applied Security GmbH / SITS AG, Großwallstadt

    Led frontend development of the public statutory health insurance portal of DASBV GmbH. Introduced state management (Redux), clean-code standards, TDD and static analysis (SonarQube); test coverage to 80%.

  3. 2018–2019

    Fullstack Developer

    mantro GmbH, Munich

    • Mobiko, employee mobility platform: designed an algorithmic solution to a variant of the knapsack problem for tax-optimized expense allocation. Angular, NestJS.
    • Jagdgefährte, hunting application: optimized database query performance, cutting request latency by 25%. NestJS, Postgres.
    • company42, industrial IoT computer-vision device: led backend development and product ownership; designed a parallelized inference layer for querying edge-deployed CV models. Go.

  4. 2017

    Frontend Engineer

    Cellebrite, Petah Tikva

    Product ownership and frontend development of a smartphone diagnostics and repair platform. Integration lead across the backend, mobile, customization and core-module teams. Led client demonstrations and restructured the customer feedback loop to bring overseas customers into development sprints, about 25% more sprint throughput.

  5. 2014–2017

    Fullstack Developer

    Matzpen, C4I Corps, IDF

    Designed and maintained the cross-network database synchronization between civilian and military networks behind the IDF's public web infrastructure. Maintained mission-critical J2EE enterprise applications. Led the modernization of a legacy monolith, migrating JSP web apps to component-based frontends in Angular and TypeScript.

Education

  1. 2023–2026

    M.Sc. Informatik, TU Munich

    Distributed Systems, Computer Networks & Architecture

    Master thesis: Revisiting Local Area Peer-to-Peer Overlays for Grassroots Social Networks. Research Fellow, TU Munich & Technion, Haifa, 2025–2026, in a research collaboration between the Technion, TU Munich and the Weizmann Institute. Details under Research.

  2. 2019–2023

    B.Sc. Informatik, TU Munich

    Bachelor thesis: Enhancing Distributed REST APIs on the Fly.

Skills

Go, Rust, TypeScript/Node.js, Python, Java, C#, Dart · React, Angular, Svelte · PostgreSQL, SQLite · Docker, Kubernetes, GCP · libp2p, BLE, UDP/QUIC, Noise · Arduino, Raspberry Pi, ESP32 · Distributed systems, Networking · AI-assisted development (Claude, Codex, Copilot)

Full CV (PDF)

Research

Grassroots Social Networking

Governments shut the Internet down during protests, and disasters cut it physically; people then turn to peer-to-peer messaging. Grassroots Social Networking is a peer-to-peer overlay for messaging and social networking that runs strictly on the smartphones of its users, with no servers, relays or shared ledgers. One application-layer overlay sits on two underlays: a BLE mesh between devices in radio range, and, when an Internet path exists, direct NAT-traversed streams between friends. Messages are relayed along the social graph only.

My thesis measures BLE link formation and multi-hop delivery on a testbed of eight commodity smartphones, and uses those measurements to parameterize simulations of the system at scale. BLE alone cannot carry a grassroots social network at scale: delivery is bounded by the radio airtime a node shares among its active links, not by range, and a second Internet underlay that bridges parts of the mesh is needed.

Joint research between the Technion, TU Munich and the Weizmann Institute.

Transport & protocol
BLE mesh underlay and an Internet underlay carrying UDX streams; NAT hole-punching and a rendezvous protocol; UDX against QUIC trade-offs; store-carry-forward buffering; relay restricted to the social graph.
Security
Public-key identities; Noise XX sessions over Curve25519 with ChaCha20-Poly1305.
Implementation
dart_libp2p; a js-libp2p bootstrap and relay node on GCP; an anchor server with deterministic subkey derivation.
Evaluation
A testbed of eight smartphones across hardware classes, with tracing instruments for link formation and clique delivery under contention; simulations of link-establishment and packet-forwarding rules, parameterized by the measured link distributions.
Current work
A NAT topology and hole-punching survey: libp2p's AutoNAT in a grassroots approach, using multiple connected friends to characterize the NAT a peer sits behind.

Simulation

The thesis simulation, in the browser. Six packet-forwarding rules carry the same message over the same BLE mesh; the panels count transmissions and duplicates, and show what each rule must know before it forwards. The engine is Go compiled to WebAssembly with TinyGo, and loads when you scroll here. The hall, load and timing differ from the thesis runs, so the numbers are the simulation's, not the thesis's.

Open the simulation on its own page

Projects

Writing & talks

    Nothing here yet.

    About

    Jerusalem, after eight years in Munich. Cycling in the Jerusalem hills. Travel planning, with an obsession for logistics and the historical layers of a place; I like telling the story of a place while standing in it. Design, craft and museums.

    Hebrew, native. English, bilingual. German, C1.

    Contact